Hepatitis C virus (HCV) is closely related to both the pestivirus and flavivirus genera in the Flaviviridae family. HCV is a single stranded RNA virus; the viral genome is approximately 9.5 kb. HCV RNA is positive sense and has a unique open reading frame which encodes a single polyprotein (Clarke. 1997. J. Gen. Virol. 78:2397). The polyprotein is proteolyticly processed to yield the mature viral proteins which include: nucleocapsid, envelope 1, envelope 2, metalloprotease, serine protease, RNA helicase, cofactor, and RNA polymerase.
HCV is a major human pathogen. The virus was found to be the cause of most cases of hepatitis which could not be ascribed to hepatitis A, hepatitis B, or hepatitis delta virus (Clarke, supra). Over fifty percent of patients with hepatitis C virus (HCV) become chronic carriers of the virus; there may be as many as 500 million chronic carriers worldwide (Dhillon and Ducheiko. 1995. Histopathology 26: 297). Persistent infection with the virus causes chronic hepatitis and may ultimately lead to cirrhosis and/or cancer (Kuo et al. 1989. Science 244:362). Current therapies for HCV are ineffective, consequently there is a need for new approaches to treat HCV infection.